Abstract：
:The radiation inactivation method was used to study the size of acetylcholine receptors in the intact membrane-bound state. This technique was reinvestigated, and modifications were made which remove substantial difficulties affecting previous applications of it to such proteins. The molecular size was deduced here by reference to a set of protein standards: an inactivation ratio was defined relative to a given internal enzyme molecular weight standard, and a linear calibration plot for the inactivation ratios of the protein standards was constructed and applied. The acetylcholine receptor in Torpedo electric organ, cat denervated muscle, and chick embryonic muscle was found by this method to exist in the membrane as a homogeneous population of the same size in each case. This receptor, when identified thus by the alpha-neurotoxin-binding target structure, has an apparent molecular weight of 300000 or a molecular volume of about 350 nm3. In comparison, the molecular weight of the cat muscle receptor when solubilized, as analyzed by gel electrophoresis after extensive cross-linking, was found to be 270000 +/- 20000. These two values are thought to be equivalent by virtue of the situation and structure of the receptor protein in the cell membrane. If a disulfide-bridge dimeric receptor exists in the membrane (as other evidence has indicated for Torpedo), each monomer acts independently there in binding alpha-neurotoxin, since the monomers can be inactivated independently by irradiation in the Torpedo membrane. In the muscle membrane no evidence for the existence of receptor dimers, of any kind, has been found.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Lo MM,Barnard EA,Dolly JOdoi
10.1021/bi00538a033subject
Has Abstractpub_date
1982-04-27 00:00:00pages
2210-7issue
9eissn
0006-2960issn
1520-4995journal_volume
21pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:The light-driven enzyme NADPH:protochlorophyllide oxidoreductase (POR) catalyzes the reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide), a key regulatory step in the chlorophyll biosynthesis pathway. As POR is light activated, it allows intermediates in the reaction pathway to be observed by initiat...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0268448
更新日期：2003-01-21 00:00:00
abstract：:The effects of solution variables on the in vitro reconstitution of calf brain tubulin, purified by the method of Weisenberg et al. (Weisenberg, R. C., Borisy, G. G., and Taylor, E. W. (1968), Biochemistry 7, 4466-4479; Weisenberg, R. C., and Timasheff, S. N. (1970), Biochemistry 9, 4110-4116), as modified by Lee et a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00627a037
更新日期：1977-04-19 00:00:00
abstract：:Here we present a biophysical, structural, and computational analysis of the directed evolution of the human DNA repair protein O(6)-alkylguanine-DNA alkyltransferase (hAGT) into SNAP-tag, a self-labeling protein tag. Evolution of hAGT led not only to increased protein activity but also to higher stability, especially...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi2016537
更新日期：2012-02-07 00:00:00
abstract：:CTP synthetase [EC 6.3.4.2, UTP:ammonia ligase (ADP-forming)] from the yeast Saccharomyces cerevisiae catalyzes the ATP-dependent transfer of the amide nitrogen from glutamine to the C-4 position of UTP to form CTP. In this work, we demonstrated that CTP synthetase utilized dUTP as a substrate to synthesize dCTP. The ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9920127
更新日期：1999-12-14 00:00:00
abstract：:The role of the peripheral reaction center chlorophyll a molecule associated with His117 of the D2 polypeptide in photosystem II was investigated in Synechocystis sp. PCC 6803 using a combination of steady state, pump-probe, and picosecond time-resolved fluorescence spectroscopy. Data were obtained from intact cells a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi000476v
更新日期：2000-11-21 00:00:00
abstract：:The C-terminal domain from the muscle protein troponin C (TnC) comprises two helix-loop-helix calcium-binding sites (residues 90-162). The assembly of these two sites is governed by calcium binding enabling a synthetic C-terminal domain to be preferentially and stoichiometrically assembled from two synthetic peptides ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9528006
更新日期：1996-06-11 00:00:00
abstract：:The structure of octylcarbamoyl-alpha-chymotrypsin to a resolution of 3.0 A is described. The n-octyl side chain of the active site directed irreversible inactivator octyl isocyanate is bound exclusively in the hydrophobic substrate binding pocket. The n-octyl isocyanate forms a planar urethane bond with the Ser-195 O...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00694a008
更新日期：1975-11-18 00:00:00
abstract：:Parkinson's disease (PD) involves loss of dopaminergic neurons in the substantia nigra and is characterized by intracellular inclusions, Lewy bodies, consisting primarily of aggregated alpha-synuclein. Two substitution mutations (A53T and A30P) in alpha-synuclein gene have been identified in familial early-onset PD. T...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi036114f
更新日期：2004-05-11 00:00:00
abstract：:The association of ferredoxin with ferredoxin:NADP+ reductase (both proteins from spinach chloroplasts) was characterized by isothermal titration calorimetry and fluorescence quenching titration. The formation of the complex is mainly driven by a positive entropy change (delta S = 125 +/- 8 J mol-1 K-1). The calorimet...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00249a019
更新日期：1994-11-15 00:00:00
abstract：:31P NMR spectra of equilibrium mixtures of enzyme-bound reactants and products of the adenylate kinase reaction (formula; see text) were analyzed by using computer simulations based on density matrix theory of chemical exchange. Since adenylate kinase has the unique feature that the reactants in the reverse direction ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00300a025
更新日期：1984-02-28 00:00:00
abstract：:We have employed high-performance liquid chromatography (HPLC) to investigate the syntheses of histones H1 and H1o as synchronized cells traverse from mitosis to S phase. Chinese hamster (line CHO) cells were synchronized by mitotic selection, and, at appropriate times, they were pulse labeled for 1 h with [3H]lysine....
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00329a031
更新日期：1985-04-09 00:00:00
abstract：:Understanding the structural basis for defects in protein function that underlie protein-based genetic diseases is the fundamental requirement for development of therapies. This situation is epitomized by the cystic fibrosis transmembrane conductance regulator (CFTR)-the gene product known to be defective in CF patien...
journal_title：Biochemistry
pub_type： 杂志文章,评审
doi：10.1021/bi702209s
更新日期：2008-02-12 00:00:00
abstract：:The location of the sites of methylation of the methyl-accepting chemotaxis proteins (MCP) of Escherichia coli has been investigated by trypsin digestion and mapping of the peptides. The two principal MCPs, MCP I and MCP II, were found to have very similar methyl-labeled peptide patterns. Each produced three major spe...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00507a051
更新日期：1981-02-17 00:00:00
abstract：:The reduced hydroxylase component (MMOH) of soluble methane monooxygenase (MMO) from Methylosinus trichosporium OB3b reacts with O2 and CH4 to produce CH3OH and H2O in a single-turnover reaction. Transient kinetic analysis of this reaction has revealed at least five and probably six intermediates during the turnover [...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi960596w
更新日期：1996-08-06 00:00:00
abstract：:Phosphofructokinase from Escherichia coli (EcPFK) is a homotetramer with four active sites and four allosteric sites. Understanding the allosteric activation of EcPFK by MgADP has been complicated by the complex web of possible interactions, including active site homotropic interactions, allosteric site homotropic int...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048569q
更新日期：2004-11-09 00:00:00
abstract：:PKC phosphorylation regulates PITX2 DNA binding and transcriptional activity. Mutation of individual PKC sites demonstrates the functional regulation of PITX2 through phosphorylation. Immunoprecipitation of PITX2 and a PITX2 PKC mutant protein reveal specific in vivo phosphorylation by PKC in transfected cells. The tr...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048362x
更新日期：2005-03-15 00:00:00
abstract：:Coiled coils are simple models for studying the association of two polypeptide chains to form a folded protein. Previous work has shown that the folding of a coiled coil can be described by a two-state transition between two unfolded monomeric peptide chains and a folded coiled coil dimer. Here we report the thermodyn...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi002161l
更新日期：2001-03-27 00:00:00
abstract：:Wideline 2H NMR spectroscopy was used to assess the conformational and orientational effects of N-acetylneuraminic acid (NeuAc) (sialic acid) as a component of a particular oligosaccharide chain at a bilayer membrane surface. For this purpose, three glycosphingolipids, sharing a neutral core tetrasaccharide and differ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi952964m
更新日期：1996-04-16 00:00:00
abstract：:Among hormone-inducible transcription factors, estrogen receptors (ERs) play important roles in tissue growth and differentiation, via either direct or indirect binding, in the nucleus, to specific DNA targets called estrogen responsive elements (EREs), or through nongenomic pathways. In humans, two estrogen receptor ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.5b00026
更新日期：2015-06-30 00:00:00
abstract：:Homology modeling was used to identify two particular residues, Glu175 and Ala176, in Pseudomonas stutzeri phosphite dehydrogenase (PTDH) as the principal determinants of nicotinamide cofactor (NAD(+) and NADP(+)) specificity. Replacement of these two residues by site-directed mutagenesis with Ala175 and Arg176 both s...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi035018b
更新日期：2003-10-14 00:00:00
abstract：:Intrinsic disorder is at the center of biochemical regulation and is particularly overrepresented among the often multifunctional viral proteins. Replication and transcription of the respiratory syncytial virus (RSV) relies on a RNA polymerase complex with a phosphoprotein cofactor P as the structural scaffold, which ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.5b01332
更新日期：2016-03-15 00:00:00
abstract：:We examined the metabolism of exogenously added 13C-labeled fructose 1,6-bisphosphate (either labeled at the first and sixth carbons or labeled at the first carbon only) and of [2-13C]glucose in well-oxygenated and well-superfused hog carotid artery segments. Exogenously added fructose 1,6-bisphosphate was utilized by...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00004a027
更新日期：1995-01-31 00:00:00
abstract：:It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge separation from P* is...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9703756
更新日期：1997-06-10 00:00:00
abstract：:A novel phosphotriesterase was recently discovered and purified from Sphingobium sp. TCM1 (Sb-PTE) and shown to catalyze the hydrolysis of a broad spectrum of organophosphate esters with a catalytic efficiency that exceeds 10(6) M(-1) s(-1) for the hydrolysis of triphenyl phosphate. The enzyme was crystallized and the...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b00364
更新日期：2016-07-19 00:00:00
abstract：:Staphylococcal nuclease H124L is a recombinant protein produced in Escherichia coli whose sequence is identical with that of the nuclease produced by the V8 variant of Staphylococcus aureus. The enzyme-metal ion activator-nucleotide inhibitor ternary complex, nuclease H124L-thymidine 3',5'-bisphosphate-Ca2+, was inves...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00453a011
更新日期：1990-01-09 00:00:00
abstract：:Acid beta-glucosidase is a lysosomal membrane protein that cleaves the O-beta-D-glucosidic linkage of glucosylceramide and aryl-beta-glucosides. Full activity reconstitution of the pure enzyme requires phospholipids and saposin C, an 80 aa activator protein. The deficiency of the enzyme or activator leads to Gaucher d...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi980785+
更新日期：1998-08-18 00:00:00
abstract：:Remodeling of photosynthetic machinery induced by growing spinach plants under low light intensities reveals an up-regulation of light-harvesting complexes and down-regulation of photosystem II and cytochrome b6f complexes in intact thylakoids and isolated grana membranes. The antenna size of PSII increased by 40-60% ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi700748y
更新日期：2007-10-02 00:00:00
abstract：:The chicken and goose egg white lysozymes (ChEWL and GoEWL) are homologues, but differ in substrate specificity. ChEWL catalyzes the hydrolysis of the glycosidic bonds of bacterial peptidoglycans and chitin-derived substrates, while GoEWL is specific for bacterial peptidoglycans. The active-site aspartate 52 residue o...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi951671q
更新日期：1996-02-13 00:00:00
abstract：:Galactosyltransferase (UDPgalactose:glycoprotein galactosyltransferase EC 2.4.1.22) was isolated from swine mesentary lymhromatography on Sepharose 4B colums containing covalently bound p-aminophenyl-beta-D-N-acetylglucosamine. The homogenous enzyme showed a single band on disc gel electrophoresis and had a specific a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00668a009
更新日期：1976-11-16 00:00:00
abstract：:Hexose-1-phosphate uridylyltransferase catalyzes the interconversion of UDP-galactose and glucose-1-P with UDP-glucose and galactose-1-P by a double-displacement mechanism through a covalent intermediate (E-UMP), in which UMP is bonded to one of two histidine residues at the active site, H164 or H166. To identify whic...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00499a003
更新日期：1990-11-27 00:00:00
